Handle possessives and plurals better

[cbizon]

"Parkinson's" returns hits, but "Parkinsons" does not. Other punctuation like commas or hyphens appear to be ignored by solr. Can we also ignore apostrophes?

Also see Alzheimer. Searching for "Alzheimer's" or "Alzheimer" returns over 20 hits, including things from CHEBI as well as MONDO. "Alzheimers" returns 1. Things like this will be handled inconsistently across naming schemes, so we should probably do some work here to make sure it doesn't matter.